Rama suddenly started getting sick after I returned home this past Monday (my roommate had been caring for him). He was looking lethargic and had some small signs of fin rot. Every since then he's been getting worse. The fin rot developed even further, he's gotten popeye, and is laying at the bottom of the tank and not eating almost all day. I have been treating him since Tuesday with a combination of Maracyn and Maracyn 2, but it hasn't seemed to have an effect thus far. Now, he's been breathing really rapidly and hard, with his little gills flapping wildly. I'm so concerned, I'm not sure if there's anything else I can do for him.

I don't have access to anything else but a PetSmart, but I'm wondering if I should get some different sort of medicine or something to treat the water . . . I'm getting pretty desperate now.

Housing
What size is your tank? 2.5 gallonsWhat temperature is your tank? 75 - 80 degrees F
Does your tank have a filter? Yes
Does your tank have an air stone or other type of aeration? No
Is your tank heated? No
What tank mates does your betta fish live with? A mystery snail and an algae ball.

Food
What type of food do you feed your betta fish? Tetra BettaMin Tropical Medley
How often do you feed your betta fish? Twice a day
Maintenance
How often do you perform a water change? Once every two weeks (or so)
What percentage of the water do you change when you perform a water change? 100%
What type of additives do you add to the water when you perform a water change? Tetra BettaSafe

Water Parameters:
Have you tested your water? If so, what are the following parameters?I haven't tested yet because I don't have the tools, but I'm taking a water sample tomorrow to PetSmart to get it tested. The water quality in the area is not great though, and is particularly hard.

Symptoms and Treatment
How has your betta fish's appearance changed? Fin rot, bulging eyes that are slightly glazed white (popeye), slightly pale
How has your betta fish's behavior changed? Lethargic, actually laying at the bottom of the tank, not eating, rapidly breathing/fins flapping wildly, looks a bit like he's gasping
When did you start noticing the symptoms? Monday or so.
Have you started treating your fish? If so, how? I have been treating with a Maracyn and Maracyn 2 combination every day. I have also been changing 25% of the water every day.
Does your fish have any history of being ill? No
How old is your fish (approximately)? I'm not sure, but I probably bought him 4 or 5 months ago.

I agree with the above. How are you monitoring temperature? Unless you keep the room he is in a constant temperature of 80F+ then he needs a heater.

Your betta has an eye and fin infection from chronic poor water conditions.

You need to increase your water changes. I get some Prime to use as your conditioner, and use a double dose on the bowl first to neutralize any ammonia in there. Then do a series of 2-3 50% changes followed by a 100% change including a thorough rinsing of everything including gravel to remove debris.

For the 50% you can leave him in the tank and 100% you need to scoop him with a solo type cup and thoroughly rinse everything, especially the gravel to remove debris.

You need to use his in tank thermometer to match the tap and get the exact same temp during a water change. Then the water should be premixed (you can use gallon water jugs from the grocery store that are rinsed in hot water only and no chems if you have nothing else) with conditioner before your fish ever feels the water. For the 100% I would also use an acclimation period of 1 hour, while the fish floats inside his cup in the cleaned tank while you add a couple tablespoons of new water every 10 minutes. Try to let as little of the cup water back into the tank as possible while releasing. Make sure the cup is opaque as well.

How are you diluting the maracyns for the tank of this size? How long has he been in treatment?

We keep our room very warm, yeah. I'm not sure of the exact temperature, because I'm in an apartment and cannot control it, but it has to be closer to 80 in here. I used to have one of those press on thermometers that stuck to the outside of the tank and it consistently read between 75 and 80 degrees without the use of a heater. But it got wet at one point and I was afraid that it wouldn't read right so I stopped using it.

I totally realize now since he's been sick that my water changes have been lacking. However, I was told that with the filter you'd only need to change the water once a month... that guy was so wrong!

I did a 100% water change at the start of the treatment and have now been doing 25% changes a day, but I'll up it to 50% a day.

I've left the filter on while putting in the Maracyns as the directions said, and I softly stir it in with a plastic spoon. He's been in treatment since Tuesday, but like I said, he doesn't look any better. He's in really rough shape, and I'm wondering if I should get a more "heavy duty" medication.

He also hasn't eaten for at least a few days. Is there any way I can get him to eat?

The swings are also very hard on him and his ideal temp is between 78-80F. His tank temp will always be several degrees below room temp. You should still get him a heater based on this info.

Do you have carbon in your filter? If you do you need to remove it or the Maracyns will do nothing.

You're not putting the whole packet of Maracyns in the 2.5g are you? How are you diluting it?

Maracyns killed your cycle so you will have to start over once he's well, but you shouldn't cycle with a sick fish.

Once he's well here is how to cycle safely: two 50% changes a week with siphon may eventually be all that's needed once it's fully established (up to 2 months or maybe even longer with such a small tank) but many will tell you that the tank is just too small to maintain a stable biofilter so testing is important if you want to try to cycle.

I'm not sure if my filter has carbon in it or not. I'm using Aqueon MiniBow filter cartridges.

No, I'm not putting the whole packet into the tank. I'm following the instructions on the packets on how much to put in - half a packet of Maracyn 2 on the first day and 1/4 a packet on subsequent days, 1/4 a packet every day of Maracyn.

So as for what I should get and do right now...

Should I buy something and use it immediately to treat the water for its poor quality based on how the water quality tests come back?

You can't dose like that. Cutting the powder is not an accurate way. You could be over or undosing him. Do 100% change to remove whatever you've added and start over. You need to dissolve the packet (which treats 10 gallons) in 10 parts of some conditioned water (say like 10 tablespoons or 10 cups.. measure exactly). Then on the first day you put a double dose so you take 5 parts (5 tablespoons or cups) of the mixture and put it in his bowl. Then on the next day you must mix it up fresh again. You cannot save the mixture and keep using it. This time you take 2.5 parts (2.5 tablespoons or cup) into his bowl.

Aqueon MiniBow filter cartridges have carbon. The filter can continue to run but the cartridge needs to be removed. The carbon just absorbs the meds and renders them useless.

As a side note, the problem with this filter is that, I belive, they only have one type of media (one type of cartridge) that must be replaced monthly because of the carbon. However, every time you replace the cartridge you restart your cycle. So personally I would get some filter sponges, cut them to size and stuff them into your filter instead of the ones that come with it. These you only need to replace once every 6 months to a year, and you should never replace everything at once. So like.. have two sponges in there and replace one at like the 11th month period and one the 12th month. To maintain sponges you only need to swish them a bit in the old tank water every week or month to keep them from getting clogged.

Get a thermometer asap. Report back on temp, but also use it to do the water changes as I said in post #3, remove the carbon then start over with correct dose of Maracyns. Do 50% change before each dose daily and 100% change on day 3 before dosage. Treat for another week with both Maracyn and Maracyn 2. Hopefully you haven't bred a resistance, but be aware you may need a different antibiotic.